Foster made his Dolphins debut as the Week 1 starter, but was waylaid by the latest in a long line of soft-tissue injuries early in the Week 2 loss to the Patriots. He will finish his brief Miami career with 55 rushing yards on 22 attempts.

Miami Dolphins running back
Arian Foster announced his retirement midway through his 8th season. Take a look at the best photos from his career.

"This game has been everything to me ... my therapy, my joy, my solace and my enemy," Foster wrote via Uninterrupted.com. "I've learned to love every facet of this game, from the peak of accomplishment to the gutter of criticism. And it all makes the ride worthwhile. I've been fortunate enough to play many successful years in this league. I've given a lot to this game and given up a lot for it. But it has returned to me more than I could have ever asked for.

"Faceless gladiators have been shuffled in and out of this arena for decades and I'm proud to have taken part in that legacy. My father always said, 'You'll know when it's time to walk away.' It has never been more clear than right now. I'm walking away with peace. I know it's not commonplace to do it midseason, but my body just can't take the punishment this game asks for any longer. ... Every athlete would love to go out as a Super Bowl MVP, riding off into the sunset with the crowd cheering their name. Unfortunately, life has other plans and they're usually opposite the imagination. But that imagination got me this far and I could not be prouder of the things my teammates and I accomplished in this game."

Foster went on to thank the Dolphins organization for allowing him to "bow out with grace."

The 30-year-old's retirement is effective immediately, NFL Network Insider Ian Rapoport reported, via a source with knowledge of the situation. Asked why Foster was retiring now, Rapoport was told the eight-year veteran's heart couldn't handle another rehab, even for a minor injury.

Undrafted out of Tennessee in 2009, the rookie bided his time on the Houston Texans' practice squad until Steve Slaton's injury granted him a late-season audition. It was immediately apparent that the smooth-gliding Foster was an upgrade as the featured back.

By the next summer's training camp, Foster had emerged as an obvious breakout candidate and the talk of fantasy football circles. Perfectly suited for Kyle Shanahan's zone-blocking scheme, Foster's patient, one-cut-and-go style resulted in a transcendent 2010 season, leading the league in rushing yards, yards from scrimmage and touchdowns.

Foster earned Pro Bowl nods in four of the next five seasons, recognition of his status as one of the most complete backs in football during the past half-decade. By the time the Texans cut ties last March, he had become the franchise's all-time leader in rushing yards, rushing touchdowns, yards per game and total scoring for a non-kicker.

How much of an impact did Foster make in his prime? Among all players with a minimum of 1,000 touches since 2010, per NFL Research, he finishes his career ranked first in yards from scrimmage per game (115.2) and 100-yard rushing games (31) and is tied for the lead in touchdowns from scrimmage (65). His 84.7 rushing yards per game rank second during that span.

A proud free-thinker in a pro football culture that often demands conformity, Foster's legacy will be as one of the most memorable characters and productive stars of his generation.